1. Field of the Invention
The present invention relates to an image reading apparatus, a default value adjusting method of an image reading apparatus, and a chart original, and in particular, relates to an image reading apparatus having default values of a resolution of a pulse motor that moves a lens unit or the like of the image reading apparatus, a default value adjusting method of an image reading apparatus which adjusts default values, and a chart original which is directly used in an embodiment of the default value adjusting method of an image reading apparatus.
2. Description of the Related Art
Japanese Patent Application Laid-Open (JP-A) No. 5-281631 discloses a method for adjusting a position of a zoom ring which adjusts the magnification of a zoom lens and a position of a focusing ring which adjusts the focusing point of the zoom lens, in accordance with the size of a photographic print. In this method, a default value of the position of the zoom ring and a default value of the position of the focusing ring, in accordance with the size of a photographic print, are recorded in advance in a memory. On the basis of these default values, the position of the zoom ring and the position of the focusing ring are controlled, an image of a photographic print is image-formed (focused) at an image sensor, and the image thus image-formed at the image sensor is displayed on a preview display apparatus. In cases in which the image displayed on the preview display apparatus is not suitable for the display screen, an operator adjusts the respective positions of the zoom ring and the focusing ring such that the image displayed on the preview display apparatus becomes suitable for the display screen, while observing the image displayed on the preview display apparatus. The already stored default value is changed to the value obtained by the adjustment of the zoom lens. As a result, since an adjusted default value in accordance with each of the photographic print sizes thereafter is used, it is not necessary to adjust the zoom lens in accordance with the size of each photographic print. The burden on the operator in terms of time and labor can be reduced.
However, in the conventional adjusting method described above, although the burden on the operator in terms of time and labor is reduced after the default value is adjusted, however, during adjustment, much time is required, since the default value must be adjusted for each size of the photographic film while viewing the display screen.